Dewatering biomass material comprising polysaccharide, method for extracting polysaccharide from biomass material, and dewatered biomass material

ABSTRACT

A process for dewatering biomass material comprising polysaccharide and water. The process comprises wetting the biomass material with a wetting composition comprising an alcohol to form a biomass slurry comprising wetted biomass material and a liquid component, mechanically separating a portion of the liquid component from the biomass slurry, and mechanically separating at least a portion of the water from the wetted biomass material. A process for extracting polysaccharide from the biomass material and a dewatered biomass material are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. patent application Ser.No. 13/665,120, filed on Oct. 31, 2012, now U.S. Pat. No. 8,764,991,issued on Jul. 1, 2014, which is a continuation of U.S. patentapplication Ser. No. 12/510,478, filed on Jul. 28, 2009, now U.S. Pat.No. 8,323,513, issued on Dec. 4, 2012, the disclosures of which areincorporated herein by reference in their entirety.

FIELD OF INVENTION

This invention relates to polysaccharide materials and more particularlyrelates to dewatering of polysaccharide containing materials.

BACKGROUND OF INVENTION

Polysaccharides such as pectin and carrageenan are useful as colloidalsin many applications including, but not limited to food preparation.Polysaccharides can be extracted from biomass materials containingpolysaccharides and such biomass materials may include citrus fruitpeel, apple pomace, sugar beet residue from sugar production, sunflowerresidue from oil extraction, potato residue from starch extraction frompotatoes, red seaweed and brown seaweed.

Some biomass materials contain juice, essential oil, sugar, water, orcombinations thereof. Often, materials such as juice, essential oils,and sugar are removed or extracted from the biomass material and thepectin is then extracted from the remaining biomass material. Suchbiomass material may contain substantial amounts of water includingwater naturally present in the material and water added to the materialduring extraction of sugar or other components.

In countries that do not have adequate domestic sources ofpolysaccharide containing biomass material, biomass material from othercountries may be imported and are often transported over long distancesfor polysaccharide extraction. Thus, it may be necessary for economicreasons to remove substantial amounts of water from the polysaccharidecontaining biomass material before transport of the biomass materialover long distances. Polysaccharide containing biomass materials aretypically dried for transportation by direct heating with combustednatural gas. Use of large quantities of water to extractnon-polysaccharide containing biomass material components such as sugarfrom biomass material and cleaning the effluent water from this processmay be economically and environmentally undesirable. Furthermore, dryingwet polysaccharide containing biomass material by direct heating withcombusted natural gas may also be economically and environmentallyundesirable. Consequently, there may be a need for a method for treatingand dewatering polysaccharide containing biomass material which usesless water, and therefore produces less effluent, or which reducesenergy consumption and emission of greenhouse gases such as CO₂, orboth.

SUMMARY OF INVENTION

This invention addresses one or more of the above-described needs byproviding a process for dewatering biomass material comprisingpolysaccharide and water, in which the process comprises wetting thebiomass material with a wetting composition comprising an alcohol toform a biomass slurry comprising wetted biomass material and a liquidcomponent, mechanically separating at least a portion of the liquidcomponent from the biomass slurry, and mechanically separating at leasta portion of the water from the wetted biomass material. Without wishingto be bound by theory, the alcohol in the wetting composition appears tofacilitate mechanical separation of water from the wetted biomassmaterial.

According to another aspect of the present invention, a process forextracting polysaccharide from a biomass material comprising thepolysaccharide in water is provided. This process comprises wetting thebiomass material with a wetting composition comprising an alcohol toform a biomass slurry comprising wetted biomass material and a liquidcomponent, mechanically separating at least a portion of the liquidcomponent from the biomass slurry, mechanically separating at least aportion of the water from the wetted biomass material to form dewateredbiomass material, and extracting at least a portion of thepolysaccharide from the dewatered biomass material.

According to still another aspect of this invention, an alcohol washedand pressed polysaccharide containing biomass material is provided. Thisbiomass material comprises dry matter in an amount from about 35 to 60%by weight of the biomass material and residual sugar in an amount fromabout 3 to 30% by weight of the biomass material.

Embodiments of this invention are set forth below in the followingdetailed description, drawings, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a four step countercurrent ethanolalcohol wash with a single pressing in accordance with an embodiment ofthis invention.

FIG. 2 is a schematic diagram of a four-step countercurrent isopropylalcohol wash with a single pressing step.

FIG. 3 is an exploded view of a pressing cell for use in pressing fruitpeel in accordance with embodiments of this invention.

FIG. 4 is a perspective view of the pressing cell in FIG. 3 mounted toan analyzer.

DETAILED DESCRIPTION OF EMBODIMENTS

As summarized herein above, this invention encompasses a method fordewatering biomass material comprising polysaccharide, a method forextracting polysaccharide from biomass material, and a dewatered biomassmaterial comprising polysaccharide.

According to embodiments of this invention, biomass materials comprisinga polysaccharide and water are dewatered for subsequent extraction of atleast a portion of the polysaccharide in the biomass material. Suitablepolysaccharide containing biomass materials include, but are not limitedto citrus fruit peel, apple pomace, from sugar beet residue from sugarextraction, sunflower residue from oil extraction, potato residue fromstarch production, and other pectin containing biomass material. Inaddition, other suitable polysaccharide containing biomass materials forembodiments of this invention include, but are not limited to redseaweed containing carrageenan and agar, and brown seaweed containingalginate.

According to certain embodiments of the present invention, suitablepolysaccharide containing biomass material includes citrus fruit peel,such as, but not limited to orange peel, lemon peel, lime peel, andgrapefruit peel. Dry citrus peel is an important raw material in themanufacture of pectin, but the cost of drying citrus peel is high andmay amount to about half of the cost of making dry citrus peel. Citruspeel has been conventionally dried with direct heating from combustingnatural gas.

Before dewatering in accordance with embodiments of this invention, thepolysaccharide containing biomass material may be subject to anextraction process to extract one or more other components of thebiomass material, such as juice and essential oils from citrus fruit,sugar from sugar beets, sunflower oils from sunflower seeds, apple juicefrom apple fruit, and starch from potatoes. Furthermore, citrus peel maybe subjected to aqueous washing for removal of sugar from the peel.

Not wishing to be bound by theory, it is believed that polysaccharidespresent in biomass material may bind water, thereby making removal ofwater from polysaccharide containing biomass material by pressingdifficult. Surprisingly, treating polysaccharide containing biomassmaterial with alcohol in accordance with embodiments of this inventioncauses the polysaccharide in situ to lose its water binding ability andthereby makes pressing possible and increases the dry matter in theproportion of the polysaccharide containing biomass material. As usedherein, dry matter refers to material in the biomass material thatremains after such material is dried at 65° C. to 70° C. for 20 to 24hours.

Prior to dewatering, the polysaccharide containing biomass material maybe comminuted by chopping, cutting, grinding, or other means. Accordingto certain embodiments, the polysaccharide containing biomass materialmay be cut to an average particle size in the range from about 10 mm toabout 30 mm, the particle size being determined by measuring the largestdimension of the particle.

According to certain embodiments of the present invention, the biomassmaterial comprising polysaccharide and water is wetted with a wettingcomposition comprising an alcohol to form a biomass slurry comprisingwetted biomass material and a liquid component. According to certainembodiments, the wetting composition is added to the biomass material inan amount sufficient to cover the biomass material. According to certainembodiments, the step of wetting the biomass material comprises washingthe biomass material with the wetting composition and may includeagitating the biomass slurry. The biomass material may be washed oncewith the wetting composition or may be washed a plurality of times withthe wetting composition. According to certain embodiments, the biomassmaterial is washed with the wetting composition 2 to 4 times. After eachalcohol wash, the process includes mechanically separating at least aportion of the liquid component from the biomass slurry and, accordingto certain embodiments, comprises draining the liquid component from thebiomass material such as with a bow sieve or other separation device.

The wetting composition comprises alcohol and suitable alcohols includebut are not limited to ethanol, isopropanol, and combinations thereof.According to certain embodiments, alcohol is present in the wettingcomposition in an amount from about 40 to about 85% by weight of thewetting composition or at least about 70% by weight of the wettingcomposition. According to certain embodiments, the wetting compositionmay also include water in addition to alcohol, and in some embodiments,water constitutes all or substantially the remainder of the wettingcomposition in addition to the alcohol.

According to certain embodiments, the pH of the liquid component of thebiomass slurry may range from about 4 to about 7, the temperature of theliquid component of the biomass slurry may range from about 20° C. toabout 50° C. or from about 20° C. to about 30° C. and the duration ofeach washing step may range from about 10 minutes to about 30 minutes orfrom about 15 minutes to about 20 minutes.

According to certain embodiments, the dewatering process furthercomprises mechanically separating at least a portion of the water fromthe wetted biomass material. Furthermore, according to certainembodiments, the dewatering process further comprises mechanicallyseparating at least a portion of the water and at least a portion of thealcohol from the wetted biomass material. In embodiments in which thewetting composition comprises alcohol and water, the alcohol may beseparated from the wetted biomass material together as an azeotrope.According to certain embodiments, this may be done by pressing thewetted biomass material. According to particular embodiments, thepressure during pressing may range from about 0.5 bar to about 8 bar orfrom about 2 bar to about 4 bar and the duration of pressing may rangefrom about 1 minute to about 25 minutes, or about 10 minutes to about 25minutes, or about 15 minutes to about 25 minutes. According to a certainembodiment, the pressing step may be carried out with a screw press.

According to a particular embodiment, the polysaccharide containingbiomass material may be subjected to a single alcohol wash with thewetting composition followed by a single pressing. When using ethanol inthis embodiment, the concentration of ethanol in the wetting compositionmay be at least 60% by weight of the wetting composition, whereas whenusing isopropanol, the concentration of the isopropanol in the wettingcomposition may be at least about 40% by weight of the wettingcomposition. However, in embodiments using more dense biomass materialsuch as sugar beet material after sugar extraction or potato pulp fromstarch production, higher alcohol concentrations and longer alcoholwashing time may be used. In such embodiments, the alcohol concentrationmay range from about 60% to about 80% by weight of the wettingcomposition or from about 70% to about 80% by weight of the wettingcomposition, the washing duration may range from about 30 minutes to 24hours, or 30 minutes to about 6 hours, or about 1 hour to about 3 hours.According to a certain embodiment, a marginally higher dry mattercontent in the biomass material may be achieve by pressing the washedand pressed biomass material a second time.

According to certain embodiments, the wetting step in the dewateringprocess may comprise washing the biomass material with the wettingcomposition a plurality of washings and the step of mechanicallyseparating at least a portion of the liquid component from the biomassslurry may comprise mechanically separating at least a portion of theliquid component from the biomass slurry after each of the plurality ofwashings.

According to particular embodiments, the plurality of washings maynumber of about 2 to about 4 consecutive steps of washing the biomassmaterial with alcohol and pressing after each wash. In this embodiment,the alcohol used may have the strength of about at least 70% by weightof the wetting composition to avoid loss of pectin, the alcohol in thewetting composition may comprise isopropanol or ethanol or both, theduration of each washing step may range from about 20 to about 30minutes for a low amount of residual sugar in the biomass material, thepH of the liquid component of the biomass slurry may range from about 4to about 7, and the temperature of the liquid component of the biomassslurry may range from about 20° C. to about 50° C. or from about 20° C.to about 30° C. According to this embodiment, pressing may be performedonce or several times. When using only two washings, two or threepressings increase the amount of dry matter in the biomass material andreduce the residual sugar content in the biomass material, but with morewashing steps, one pressing step may be adequate. According to thisembodiment, the duration of pressing the biomass material may range fromabout 1 minute to about 25 minutes or 15 minutes to about 25 minutes andthe pressure applied may range from about 0.5 bar to about 8 bar or fromabout 2 bar to about 4 bar.

According to a certain embodiment, the plurality of washings may beconducted countercurrently followed by a single pressing step at theend. According to this embodiment, the number of countercurrent washingsmay range from about 2 to about 4, the alcohol concentration in thefirst of the washings may range from about 40% to about 50% by weight ofthe wetting composition or about 45% to about 50% by weight of thewetting composition as measured on gas chromatography, the alcoholconcentration in the wetting composition in the last washing may beabout 80% by weight of the wetting composition. According to thisembodiment, suitable alcohols may be isopropanol or ethanol or acombination of both, the duration of each washing step may range fromabout 10 minutes to about 30 minutes or from about 15 minutes to about20 minutes, the pH of the liquid component of the biomass slurry mayrange from about 4 to about 7, and the temperature of the liquidcomponent of the biomass slurry may range from about 20° C. to about 50°C. or from about 20° C. to about 30° C. According to this embodiment,the pressing step may be carried out on any industrial pressing deviceand the duration of the pressing step may range from about 1 minute toabout 25 minutes or from about 10 minutes to about 25 minutes. Accordingto a certain embodiment, the pressing device may be single screwpress-type using a counter pressure in the range from about 0.5 bar toabout 4 bar or from about 2 bar to about 4 bar.

According to certain embodiments, the step of mechanically separating atleast a portion of the water from the wetted biomass material is carriedout such that the dewatered biomass material comprises dry matter in anamount from about 35% to about 60% by weight of the dewatered biomassmaterial or from about 45% to about 60% by weight of the dewateredbiomass material. In addition, according to certain embodiments, theresidual sugar in the dewatered biomass material ranges from about 3% toabout 30%, or from about 3% to about 20%, or from about 3% to about 15%by weight of the dewatered biomass material.

When the dry matter is present in the dewatered biomass material in anamount of at least about 45%, or from about 45% to about 60%, or fromabout 45% to about 55% by weight of the dewatered biomass material, thedewatered biomass material is combustible without further drying.According to certain embodiments of this invention, the process fordewatering biomass material may further comprise combusting at least aportion of the dewatered biomass material to form heat and this heat maybe used in the dewatering process, such as to heat the wettingcomposition or in certain embodiments, dry the dewatered biomassmaterial, or in other heating applications. According to certainembodiments, such a heating system may be supplemented by combustingother biomass materials such as sugar cane waste or wood. Thus,according to a certain embodiment of this invention, the dewateringprocess may further comprise drying the biomass material with heat afterthe step of mechanically separating at least a portion of the water fromthe wetted biomass material to form dried dewatered biomass material.Likewise, this dried dewatered biomass material may be combusted to formheat and the heat may be used in the dewatering process. Drying thedewatered biomass material may reduce the cost of transporting thedewatered biomass material over long distances. According to anotherembodiment, heat produced from dewatered biomass may be used inapplications other than the biomass dewatering process to furtherdecrease the need for other heat or energy producing resources such asoil, natural gas, and the like.

According to embodiments of this invention, the dewatered biomassmaterial may be used in the production of polysaccharides. According toa particular embodiment, a process for extracting polysaccharides from abiomass material comprising polysaccharide and water comprises wettingthe biomass material with a wetting composition comprising an alcohol toform a biomass slurry comprising wetted biomass material and a liquidcomponent, mechanically separating at least a portion of the liquidcomponent from the biomass slurry, mechanically separating at least aportion of the water from the wetted biomass material to form dewateredbiomass material, and extracting at least a portion of thepolysaccharide from the dewatered biomass material. In accordance with acertain embodiment, the steps of wetting and mechanically separating areconducted at a first location, the polysaccharide extracting step isconducted at a second location removed from the first location, and theprocess further comprises transporting at least a portion of the drieddewatered biomass material from the first location to the secondlocation. The resulting dewatered biomass material may be transportedover long distances at more economical prices than biomass materialdewatered by conventional means.

In accordance with another embodiment, the polysaccharide extractionprocess may further comprise drying the biomass material with heat afterthe step of mechanically separating at least a portion of the water fromthe biomass material to form dried dewatered biomass material. This mayfurther reduce the cost of transporting the dried dewatered biomassmaterial.

Furthermore, the polysaccharide resulting from extraction in accordancewith such embodiments of this invention may be characterized by theidentical or similar quality as polysaccharides obtained from the samestarting materials, but without having undergone the process describedby such embodiments of the present invention.

In addition, there are several effective uses of alcohol washed andpressed polysaccharide containing biomass material in accordance withembodiments of this invention. Such embodiments include the use ofalcohol washed and pressed polysaccharide containing biomass material infood and non-food products. As used herein, food products include solid,liquid, semi-solid, gelatinous, and flowable foods, and encompassesbeverages. Embodiments of this invention include a method for preparinga food comprising adding alcohol washed and pressed polysaccharidecontaining biomass material to a food base material. Suitable food basematerials include any edible materials including but not limited towater, dairy products, confections, fruit juices, vegetable juices,sauces, syrups, bakery products, and the like.

The lower cost of dewatering biomass material in accordance with theembodiments of this invention may make use of the dewatered biomassmaterial more economical for certain lower cost application such asalkalinity controlling applications. One such application encompassesthe use of alcohol washed and pressed polysaccharide containing biomassmaterial in animal farms to neutralize ammonia and another is the use ofalcohol washed and pressed polysaccharide containing biomass material tocontrol the skin pH of animals or humans. Such an application in poultryfarms may reduce or eliminate hock burns. Thus, one embodiment of thisinvention is a method for controlling the pH of animal or human skincomprising exposing to the skin a composition comprising an alcoholwashed and pressed polysaccharide containing biomass material. Anotherembodiment is a method for controlling airborne ammonia at animal farmscomprising exposing animal waste discharged by animals at the animalfarm to a composition comprising the alcohol washed and pressedpolysaccharide containing biomass material.

According to embodiments of this invention, the alcohol washed andpressed polysaccharide containing biomass material may be used in wetform or dry form in applications described above. According to certainembodiments, the alcohol washed and pressed polysaccharide containingbiomass material may be ground, and in particular embodiments may beground to flour like consistency.

Turning to FIGS. 1 and 2, four step countercurrent alcohol washdewatering processes are illustrated in accordance with certainembodiments of this invention. The processes illustrated in FIGS. 1 and2 are identical except that different alcohols are used. Isopropanol isused in the process illustrated in FIG. 1 and ethanol is used in theprocess illustrated in FIG. 2. Accordingly, the reference numerals arethe same for both figures and the process is described only oncehereinbelow in regard to these FIGS. 1 and 2. Both of these figures alsoillustrate a mass balance which is described further hereinbelow in thedescription of the examples of certain embodiments of the invention.

FIGS. 1 and 2 both illustrate a dewatering process schematic 10 whichbegins with citrus peel 12 being added to a first wash 14 comprisingalcohol. Effluent 16 from the first wash 14 is discharged from thesystem and orange peel from the first wash 18 is delivered to the secondwash 20 which also comprises alcohol. Effluent 22 from the second washis fed back to the first wash 14 in countercurrent fashion. The orangepeel from the second wash 24 is fed to the third wash 26 which comprisesalcohol and effluent 28 from the third wash 26 is fed countercurrentlyto the second wash 20. Orange peel 30 from the second wash 26 is fed tothe fourth wash 32 which comprises alcohol. Effluent 34 from the fourthwash 32 is fed to the third wash 26. Orange peel 36 from the fourth wash32 is fed to a pressing station 38 and the effluent 40 from the pressingstation 38 is fed countercurrently to the third wash 26 as well. Alcohol42 is added to the system via the fourth wash 32. The pressing station38 discharges dewatered orange peel 44.

EXAMPLES

The present invention is further illustrated by the following examples,which are not to be construed in any way as imparting limitations uponthe scope thereof. On the contrary, it is to be clearly understood thatresort may be had to various other embodiments, modifications, andequivalents thereof which, after reading the description therein, maysuggest themselves to those skilled in the art without departing fromthe scope of the appended claims. Unless otherwise specified, %'s are byweight.

Test Procedures

Test procedures used to evaluate samples from embodiments of thisinvention in accordance with the Examples were as follows:

Determination of Degree of Esterification (DE) and Galacturonic Acid(GA) in Non-Amide Pectin

Apparatus:

-   -   1. Analytical balance    -   2. Glass beaker, 250 ml, 5 pieces    -   3. Measuring glass, 100 ml    -   4. Vacuum pump    -   5. Suction Flask    -   6. Glass filter Crucible no. 1 (Büchner funnel and filter paper)    -   7. Stop watch    -   8. Test tube    -   9. Drying cabinet at 105° C.    -   10. Desiccator    -   11. Magnetic stirrer and magnets    -   12. Burette (10 ml, accuracy±0.05 ml)    -   13. Pipettes (20 ml: 2 pieces, 10 ml: 1 piece)    -   14. pH-meter/auto burette or phenolphthalein        Chemicals:    -   1. Carbon dioxide-free water (deionized water)    -   2. Isopropanol (IPA), 60% and 100%    -   3. Hydrochloride (HCl), 0.5 N and fuming 37%    -   4. Sodium hydroxide (NaOH), 0.1 N (corrected to four decimals,        e.g. 0.1002), 0.5 N    -   5. Silver nitrate (AgNO₃), 0.1 N    -   6. Nitric acid (HNO₃), 3 N    -   7. Indicator, phenolphthalein, 0.1%        Procedure—Determination of % DE and % GA        (Acid alcohol: 100 ml 60% IPA+5 ml HCl fuming 37%):    -   1. Weigh 2.0000 g pectin in a 250 ml glass beaker.    -   2. Add 100 ml acid alcohol and stir on a magnetic stirrer for 10        min.    -   3. Filtrate through a dried, weighed glass filter crucible.    -   4. Rinse the beaker completely with 6×15 ml acid alcohol.    -   5. Wash with 60% IPA until the filtrate is        chloride-free*(approximately 500 ml).    -   6. Wash with 20 ml 100% IPA.    -   7. Dry the sample for 2½ hours at 105° C.    -   8. Weigh the crucible after drying and cooling in desiccator.    -   9. Weigh accurately 0.4000 g of the sample in a 250 ml glass        beaker.    -   10. Weigh two samples for double determination. Deviation        between double determinations must max. be 1.5% absolute. If        deviation exceeds 1.5% the test must be repeated.    -   11. Wet the pectin with approx. 2 ml 100% IPA and add approx.        100 ml carbon dioxide-free, deionized water while stirring on a        magnetic stirrer.

-   *(Chloride test: Transfer approximately 10 ml filtrate to a test    tube, add approximately 3 ml 3 N HNO₃, and add a few drops of AgNO₃.    The filtrate will be chloride-free if the solution is clear,    otherwise there will be a precipitation of silver chloride.)

-   The sample is now ready for titration, either by means of an    indicator or by using a pH-meter/auto burette.    Procedure—Determination of % DE only    (Acid alcohol: 100 ml 60% IPA+5 ml HCl fuming 37%):    -   1. Weigh 2.00 g pectin in a 250 ml glass beaker.    -   2. Add 100 ml acid alcohol and stir on a magnetic stirrer for 10        min.    -   3. Filtrate through a Buchner funnel with filter paper.    -   4. Rinse the beaker with 90 ml acid alcohol.    -   5. Wash with 1000 ml 60% IPA.    -   6. Wash with approximately 30 ml 100% IPA.    -   7. Dry the sample for approximately 15 min. on Buchner funnel        with vacuum suction.    -   8. Weigh approximately 0.40 g of the sample in a 250 ml glass        beaker.    -   9. Weigh two samples for double determination. Deviation between        double determinations must max. be 1.5% absolute. If deviation        exceeds 1.5% the test must be repeated.    -   10. Wet the pectin with approximately 2 ml 100% IPA and add        approx. 100 ml deionized water while stirring on a magnetic        stirrer.

-   The sample is now ready for titration, either by means of an    indicator or by using a pH-meter/auto burette.

-   Note: It is very important that samples with % DE<10% are titrated    very slowly, as the sample will only dissolve slowly during    titration.    Titration using indicator:    -   1. Add 5 drops of phenolphthalein indicator and titrate with 0.1        N NaOH until change of color (record it as V1 titer).    -   2. Add 20.00 ml 0.5 N NaOH while stirring. Let stand for exactly        15 min. When standing, the sample must be covered with foil.    -   3. Add 20.00 ml 0.5 N HCl while stirring and stir until the        color disappears.    -   4. Add 3 drops of phenolphthalein and titrate with 0.1 N NaOH        until change of color (record it as V2 titer).        Blind test (Double determination is carried out):    -   Add 5 drops phenolphthalein to 100 ml carbon dioxide-free or        dionized water (same type as used for the sample), and titrate        in a 250 ml glass beaker with 0.1 N NaOH until change of color        (1-2 drops).    -   Add 20.00 ml 0.5 N NaOH and let the sample stand untouched for        exactly 15 minutes. When standing the sample must be covered        with foil.    -   Add 20.00 ml 0.5 N HCl and 3 drops phenolphthalein, and titrate        until change of color with 0.1 N NaOH (record it as B1). Maximum        amount allowed for titration is 1 ml 0.1 N NaOH. If titrating        with more than 1 ml, 0.5 N HCl must be diluted with a small        amount of deionized water. If the sample has shown change of        color on addition of 0.5 N HCl, 0.5 N NaOH must be diluted with        a small amount of carbon dioxide-free water. Maximum allowed        dilution with water is such that the solutions are between 0.52        and 0.48 N.        Titration using pH-meter/Auto burette:        Using Auto burette type ABU 80 the following settings may be        applied:

Sample with % DE < 10 Blind test Proportional band 0.5 5 Delay sec. 50 5Speed - V1 10 5 Speed - V2 15 5

-   -   1. Titrate with 0.1 N NaOH to pH 8.5 (record the result as V1        titer).    -   2. Add 20.00 ml 0.5 N NaOH while stirring, and let the sample        stand without stirring for exactly 15 minutes. When standing the        sample must be covered with foil.    -   3. Add 20.00 ml 0.5 N HCl while stirring and stir until pH is        constant.    -   4. Subsequently, titrate with 0.1 N NaOH to pH 8.5 (record the        result as V2 titer).        Blind test (Double determination is carried out):    -   1. Titrate 100 ml carbon dioxide-free or deionized (same type as        used for the sample) water to pH 8.5 with 0.1 N NaOH (1-2        drops).    -   2. Add 20.00 ml 0.5 N NaOH while stirring and let the blind test        sample stand without stirring for exactly 15 min. When standing        the sample must be covered with foil.    -   3. Add 20.00 ml 0.5 N HCl while stirring, and stir until pH is        constant.    -   4. Titrate to pH 8.5 with 0.1 N NaOH (record it as B1). Maximum        amount allowed for titration is 1 ml 0.1 N NaOH. If titrating        with more than 1 ml, 0.5 N HCl must be diluted with a small        amount of deionized water. If pH does not fall to below 8.5 on        addition of 0.5 N HCl, 0.5 N NaOH must be diluted with a small        amount of carbon dioxide-free water. Maximum allowed dilution        with water is such that the dilutions are between 0.52 and 0.48        N.        Calculation:        V _(t) =V ₁+(V ₂ −B ₁)        % DE(Degree of Esterification)={(V ₂ −B ₁)×100}/V _(t)        % DFA(Degree of Free Acid)=100−% DE        % GA*(Degree of Galacturonic acid)=(194.1×V _(t) ×N×100)/400        *On ash- and moisture-free basis

-   194.1: Molecular weight for GA

-   N: Corrected normality for 0.1 N NaOH used for titration (e.g.    0.1002 N)

-   400: weight in mg of washed and dried sample for titration    % Pure pectin={(acid washed, dried amount of pectin)×100}/(weighed    amount of pectin)    Determination of Residual Sugar in Peels    Apparatus    -   1. Glass beaker, 400 ml    -   2. Balance (accuracy 0.2 g)    -   3. Magnet stirrer    -   4. Magnet    -   5. Paper filters (coarse) e.g. type AGF 614    -   6. Drying cabinet at 65-70° C.    -   7. Büchner funnel    -   8. Vacuum pump        Solutions    -   1. Isopropanol 50%        Procedure    -   1. Weigh out about 3 g dry peel in a glass beaker.    -   2. Add 100 ml 50% isopropanol.    -   3. Stir for 4 hours on magnet stirrer and filter.    -   4. Wash the filtrate with 250 ml 50% isopropanol.    -   5. Place filter and filtrate in drying cabinet at 65-70° C.        overnight and determine weight of filtrate.        Calculate the Residual Sugar in Peels:        (Weight of dry peel−weight of dry, washed peel)×100/weight of        dry peel        Determination of Molecular Weight, Intrinsic Viscosity and        Molecular Weight Distribution in Pectin Based on Orange, Lime        and Lemon.

-   The molecules are separated according to their size by gel    permeation chromatography Size Exclusion Chromatography. The    effluent from the chromatography column passes three detectors,    Refractive Index (RI), Right Angle Laser Light Scattering (RALLS)    and a viscosity detector (DP). The Viscotek software converts the    detector signals to molecular weight and intrinsic viscosity and    calculates weighted averages for the entire population.    Principle

-   The analyses are performed using SEC (Size Exclusion    Chromatography). The principle of SEC is that the molecules are    separated on basis of size, the larger molecules eludes first, then    the smaller molecules, then salts.    Equipment Analysis and Conditions.

-   Viscotek Tri-Sec instrument

-   Viscotek pump VE 1121 GPC pump

-   Degasser

-   Auto sampler AS3500 with Sample prep. module, Thermo Separation    Products

-   Column oven for 3 columns, STH 585 (40° C.)

-   3 TSK Columns GMPWXL, from Supelco and a guard column.

-   RALLS detector, Right Angle Laser Light Scattering Detector LD 600

-   Dual Detector, RI Detector, Refractive Index and Viscometer    Detector, Module 250

-   Data Manager, Acquisition Unit

-   Computer, Tri-Sec software

-   Solvent: 0.3 M Li— acetate buffer pH 4.8.

-   Flow: 1.0 ml/min

-   Pectin conc.: Approximately 1 mg/ml

-   Temperature: 40° C.

-   Injection volume: 100 μl Full loop.

-   Analysis time for one run is 50 minutes. Samples are tested by    making two runs and comparing them. If there is more than 10 percent    deviation (% STDV) between the Mw results, two new runs are made.    Manual Sample Preparation:

-   Samples known to contain non-soluble material must be manually    dissolved and filtrated (0.45 μm filter) prior to injection.    -   1. 40.0 mg sample is weighed out into a 100 ml Blue Cap bottle.    -   2. A magnet and 100 ml ethanol are added.    -   3. The sample is placed at a magnetic stirrer including a 75° C.        water bath or Block heater.    -   4. While gently stirring, 40 ml of solvent is added.    -   5. The bottle cap is closed and the sample is stirred gently at        75° C. for 30 min.    -   6. The sample is cooled in an approx. 20° C. water bath until        room temperature is reached.        Sample preparation using auto sampler AS3500:

-   Weigh out approx. 1.5 mg pectin in an auto sampler vial. This is    placed in the auto sampler rack. Use template 4 from the AS3500 auto    sampler. The following units in the auto sampler are used:

-   Dilution cycles: 3

-   Heater: ON Temp: 70° C.

-   1—Load 20 μl solvent S-1 (S-1=96% ethanol)

-   5—Add 10 μl to sample

-   11—Load 1500 μl solvent S-2 (S-2=0.3 M Li-acetate buffer)

-   15—Add 1300 μl to sample (0.1% pectin solution −1 mg/ml)

-   16—Mix for 9.9 minute

-   18—Mix for 9.9 minute

-   19—wait for 5.0 min.

-   Enable Overlay: YES (starts the next sample preparation before end    of analysis for running sample)

-   Run time at the auto sampler is set at 50 min or more. 100 ml full    loop injection is used. When the auto sampler is used, the sample is    automatically filtrated by a 0.5 mm in-line filter placed after the    auto sampler loop. As control sample, use a Dextran with the    molecular weight 70,000 Daltons, concentration about 3.0 mg/ml and a    pectin sample with a known Mw. In addition the RI detector, the    recovery, must be controlled with a pectin solution with a known    concentration. For daily control use the Dextran standard. For    weekly control use the pectin sample. For monthly control of the    recovery use the pectin solution. Dextran T 70 Mw 70,000 and    Pullulan Mw 212,000 are used for calibration. Calibration is only    performed by a Viscotek supervisor.

-   For registration of instrument-data, maintain a logbook with data    about purging, flow, pump pressure, oven temperature, detector    signals, bridge balance and recovery.

-   Eluent preparation 1 L

-   30,603 g Lithium acetate dihydrate M=102.01

-   17,157 ml (18.02 g) 100% acetic acid

-   MilliQ-water up to 1 L

-   0.25 g Sodiumazid for preservation

-   Ultra filtration 0.2μ after dissolution

-   All chemicals must be analytical grade.    Approval Criterion

-   To test a sample, always make double determination and compare    results. If there is more than 10 percent deviation (% STDV) between    the Mw results, a new double determination must be made. For pectin    standards the approval criterion is 10 percent (% STDV) at the Mw    result. For Dextran 70,000 Daltons the approval criterion is 5    percent deviation to the standard molecular weight at the Mw result.    Determination of Calcium Sensitivity    Principle

-   A fixed amount of pectin is dissolved in hot water and solution pH    is adjusted to 3.60 using 3.0M acetate buffer. Subsequent addition    of 272 ppm calcium increases the viscosity. The calcium sensitivity,    CS-99-2, is defined as the viscosity (in centipoises) for this    solution after 19 hours at 5° C.    Apparatus    -   1. Viscosity glasses, 48 mm internal diameter, height 110 mm    -   2. Magnetic stirrer    -   3. Magnetic stir bars, triangular: length 40 mm, side 6 mm    -   4. Water bath (75° C.) with magnetic stirrer or appropriate        stirring block thermostat    -   5. Foil or other heat tolerant covering material, e.g. watch        glasses    -   6. Volumetric pipettes 5 and 20 ml (or adequate dispensers)    -   7. Volumetric flasks: 2000 ml (or 5000 ml)    -   8. pH-meter with combination electrode    -   9. Laboratory scale    -   10. Fume hood    -   11. Brookfield LVT Viscometer without protective loop        Chemicals    -   Isopropanol (2-propanol), 100%    -   Calcium chloride dihydrate (CaCl₂, 2H₂O)    -   Sodium acetate trihydrate (C₂H₃NaO₂, 3H₂O)    -   Acetic acid (C₂H₄O₂), >99%    -   Ion-exchanged water        Reagents    -   3.0M sodium acetate buffer pH 3.60 (2000 ml)        -   Dissolve 81.64 g sodium acetate trihydrate in approx. 1200            ml ion exchanged water in a volumetric beaker. Transfer this            solution quantitatively to a 2000 ml volumetric measuring            flask.        -   In a fume hood, add 309 ml acetic acid. Mix the contents and            add ion-exchanged water to 2000 ml. Solution pH should be            3.60±0.05 and must be verified prior to use.    -   M sodium acetate buffer pH 3.60 (5000 ml)        -   Dissolve 204.00 g sodium acetate trihydrate in approx. 1200            ml ion exchanged water in a volumetric beaker. Transfer this            solution quantitatively to a 5000 ml volumetric measuring            flask.        -   In a fume hood, add 772 ml acetic acid. Mix the contents and            add ion-exchanged water to 5000 ml. Solution pH should be            3.60±0.05 and must be verified prior to use.    -   Calcium chloride solution        -   Weigh 32.0 g calcium chloride dihydrate into a weighing dish            or volumetric beaker and transfer quantitatively to a 1000            ml volumetric measuring flask. Add approximately 200 ml ion            exchanged water, mix the content, and add ion-exchanged            water to 1000 ml.            Procedure    -   1. Weigh pectin into a viscosity glass; for un-standardized        pectin: 0.64 g (i.e. 0.4%), and for standardized pectin: 0.80 g        (i.e. 0.5%)    -   2. Add 5.0 ml is isopropanol.    -   3. Stir the sample at a magnetic stirrer while adding 130 ml        boiling (>85° C.) H₂O. It is important that the viscosity glass        is covered (with e.g. foil) during all agitation steps, i.e.        (3)-(5).    -   4. Add 20 ml 3.0 M sodium acetate buffer pH 3.60 within 1 min        after water addition (3).    -   5. Within 1 min after (4), place the sample in a water bath at        75° C. with continued magnetic stirring for 10±2 min.    -   6. If the sample contains visual lumps, the sample must be        discarded, and the complete dissolving procedure must be        repeated.    -   7. Stir the sample with vortex of approx. 2 cm. Add swiftly        (within 2 sec) 5 ml calcium chloride solution to the sample and        mix for approx. 10 sec.        Important

-   If the vortex disappears while the calcium is added and/or local    gelation or entrapped air bubbles are observed, the sample must be    marked pre-gelled as a result of the analysis. Notably, leaving the    sample with the intention of spontaneous bubble disappearance and    proceeding as for “normal” samples, the obtained result will be too    low. In such cases, the analysis might be performed using a lower    pectin concentration.    -   1. Remove the magnet in order not to decrease viscosity prior to        its measurement and cover the glass with e.g. foil.    -   2. Within 5 min from (7), place the sample in a 5° C. water bath        for 19±3 hours. Make sure that the water level of water bath is        equal to the level of the sample surface.    -   3. If air bubbles are present at the sample surface, gently        remove these prior to viscosity measurements using a Brookfield        LVT Viscometer without its protective loop. Measure sample        viscosity at 5° C. using spindle No. 2 and spindle speed 60 rpm.        Take the Viscometer reading after 1 min.    -   4. If reading is below 10, change to spindle No. 1 and        re-measure at 60 rpm after 1 min.    -   5. If reading is above 100, place the sample in the 5° C. water        bath for 19±3 hours and re-measure the 1-min viscosity using        spindle No. 3 at 60 rpm.    -   6. Calculate the viscosity in centipoises by multiplying the        Viscometer reading by the appropriate spindle-dependent factor.        The CS value is equal to the calculated viscosity.        Determination of is Isopropanol in Wetting Composition        Principle

-   Samples are analyzed on gas chromatograph. The individual samples    are added a solution of tert butanol.    Apparatus    -   Analytical balance    -   Auto pipette    -   Pipettes    -   50 and 100 ml measuring flasks        Chemicals    -   Is propyl alcohol, analytical grade    -   Tert butanol, analytical grade    -   Deionised water        Procedure    -   1. Weigh about 5.0000 g of wetting composition into a 100 ml        measuring flask containing about 20 ml deionised water, and        weight the contents with four decimals    -   2. Fill the flask to the mark with deionised water    -   3. Transfer 5 ml to a 50 ml measuring flask containing 10 ml 2%        (w/v) tert butanol.    -   4. Fill the flask to the mark with deionised water    -   5. Transfer samples to vials and inject three times per vial    -   6. Make up standard samples containing 0.1, 0.2, 0.3 and 0.4%        (w/v) isopropanol and 0.4% tert butanol

Procedure for Treating Peel in Examples

In the following Examples, fruit was processed in laboratory scaleexperiments, pilot plant scale experiments with consecutive washing andpressing, and pilot plant scale experiments with countercurrent washingand pressing. In addition, pectin was extracted in laboratory scaleexperiments and pilot plant scale experiments. Those procedures were asdescribed below:

Treatment of Peel in Laboratory Scale

-   -   1. Apparatus    -   2. Potato peeler    -   3. Glass beakers—1000 ml, 2000 ml    -   4. Hand held juicer    -   5. pH-meter    -   6. TA-XT2 Texture Analyser, Stable Micro Systems    -   7. Load cells—25 kg, 50 kg.    -   8. Press cell 60 illustrated in FIGS. 3 and 4. The press cell 60        comprises a pedestal 62, a sieve plate 64 mounted in the        pedestal, a cylinder 66 for engaging the pedestal and holding        the peel, and a plunger 68 for pressing the peel in the cylinder        66 against the sieve plate 64. The pedestal 62 comprises a base        70 and a hollow cylindrical tube 72 extending upwardly from the        base 70 having a first compartment 74 for received liquid        removed by pressing the peel. The sieve plate 64 has 1 mm holes        through which pressed liquid passes and rests on a shoulder (not        shown) within the first compartment 74 of the tube 72 near the        top 76 of the tube 72. The peel holding cylinder 66 has a second        compartment 78 for receiving the peel and the plunger 68 has a        diameter of 28 mm and is reciprocably engaged within the peel        holding cylinder 66 through a top opening 80 in the peel holding        cylinder. The entire press cell is mounted to a TA-XT2 Texture        Analyser 82 (item 6 in this list) for pressing the peel.        Materials    -   1. Fresh lemon and oranges purchased in the local supermarket    -   2. Demineralized water    -   3. 96% ethanol    -   4. 100% iso propanol    -   5. 10% nitric acid        Procedure    -   1. The flavedo of the fruit was peel off    -   2. The fruit was juiced    -   3. The juiced fruit was cut into small cubes of about 5 mm    -   4. The cut fruit pieces were washed and pressed    -   5. The pressed fruit pieces were dried over night at about 68°        C.        With a load cell of 25 kg, the pressure used was about 4 Bar and        with a load cell of 50 kg, about 8 Bar.        Treatment of Peel in Pilot Plant Scale—Consecutive Washing and        Pressing        Equipment:    -   100 liter plastic containers    -   Pilot plant scale    -   Stirrer, IKA Werke RW 44, Germany    -   Vincent screw press P-4, USA    -   Density measuring device    -   25 liter extraction vessel        Materials:    -   Juiced orange peel obtained from Futura, Grøntorvet, Denmark    -   Demineralized water    -   80% iso propanol    -   Concentrated nitric acid    -   Ion exchange resin, Lewatit S-1468, LANXESS, Leverkusen, Germany    -   Filter aid, diatomaceous earth        Washing and pressing of peel    -   1. Upon arrival, the juiced orange peel was submerged and        stirred in 80% IPA for 30 minutes    -   2. The washed peel was pressed on Vincent screw press with a        back pressure of 4 bars    -   3. The pressed peel was covered with 80% IPA and washed in 80%        IPA for another 30 minutes    -   4. The washed peel was pressed on Vincent screw press with a        back pressure of 4 bars    -   5. The washing and pressing cycle was continued until the dry        matter of the pressed peel was constant    -   6. For some runs, the pressed peel was dried and a standard        pectin extraction performed:        -   18 liters demineralised water        -   80 ml nitric acid        -   Extraction for 7 hours at 70° C.        -   Ion exchange with 50 ml ion exchange resin for 30 minutes            while stirring        -   Precipitation with three volumes 80% IPA            Treatment of Peel in Pilot Plant Scale—Countercurrent

-   This pilot scale was conducted in accordance with the schematic    diagram in FIG. 2.    Equipment:    -   100 liter plastic containers    -   Pilot plant juicer, Otto 1800, Centenario, Brazil    -   Pilot plant scale    -   Stirrer, IKA Werke RW 44, Germany    -   Vincent screw press P-4, Vincent Corporation, USA    -   Cutter, Rex-cutter, 30 liter, Kilia, Germany    -   Density measuring device    -   25 liter extraction vessel    -   Büchner funnel        Materials:    -   Fresh oranges obtained from Futura, Grøntorvet, Denmark    -   Demineralized water    -   96% ethanol, WWR International ApS, Denmark    -   Concentrated nitric acid    -   Ion exchange resin, Lewatit S-1468, LANXESS, Leverkusen, Germany    -   Filter aid, diatomaceous earth, Celite 545        Washing and Pressing of Peel    -   7. Fresh oranges were juiced on the juicer    -   8. About 20 kg peel was cut on the cutter to a particle size of        about 10 mm, and was submerged in 80% ethanol about 20 minutes        with slight agitation.    -   9. The peel was drained for alcohol.    -   10. The drained and cut peel was washed for 20 minutes with        ethanol while stirring, either fresh 80% or ethanol from        subsequent washing steps and drained on sieve.    -   11. After five washing steps in countercurrent, the last batch        of washed peel was pressed on Vincent screw press with a back        pressure of 4 bars    -   12. For some runs, the pressed peel was dried and a standard        pectin extraction performed:        -   18 liters demineralized water        -   80 ml nitric acid        -   Extraction for 7 hours at 70° C.        -   Ion exchange with 50 ml ion exchange resin for 30 minutes            while stirring        -   Precipitation with three volumes 80% IPA            Extraction of Pectin in Laboratory Scale            Apparatus    -   1. Glass beaker—2000 ml    -   2. Büchner funnel    -   3. Stirrer with propeller stirrer, Eurostar digital, IKA Werke    -   4. Nylon cloth        Chemicals    -   1. Demineralized water    -   2. 62% nitric acid    -   3. Diatomaceous earth    -   4. Ion exchange resin, Amberlite SR1L, produced by Rohm&Haas    -   5. 100% iso propanol    -   6. 60% iso propanol        Procedure    -   1. About 900 ml demineralised water was heated to 70° C. in a        glass beaker equipped with a stirrer and temperature control    -   2. About 20 g dry peel was added to the water, and the pH is        adjusted to 1.7-1.8 by addition of 62% nitric acid.    -   3. Extraction was carried out at 70° C. for 5 hours while        stirring.    -   4. After extraction, the content of the vessel was filtered on a        Buchner funnel using diatomaceous earth as filter aid previously        rinsed with a mixture of 10 ml 62% nitric acid and 500 ml        demineralised water.    -   5. The filtered extract was ion exchanged while stirring by        adding about 50 ml resin (Amberlite SR1L, produced by Rohm&Haas)        per liter of filtered extract. While stirring, the ion exchange        was carried out during 20 minutes while stirring.    -   6. The ion exchanged filtrate was filtered on a Buchner funnel        equipped with a cloth.    -   7. The filtered ion exchanged filtrate was precipitated by        adding it to three parts of 100% isopropanol while stirring        gently.    -   8. The precipitate was collected on nylon cloth and pressed by        hand to remove as much isopropanol as possible.    -   9. The hand pressed precipitate was washed once in 60%        isopropanol and then dried at about 68° C. in a drying cabinet        at atmospheric pressure.    -   10. After drying, the pectin was milled.        Extraction of Pectin in Pilot Plant Scale    -   1. 600 g dry peel, 18 liter ion exchanged water and 80 ml 62%        nitric acid were mixed in an 18 liter extraction vessel and        extracted for 7 hours at 70° C. while stirring.    -   2. The mixture was filtered on Buchner funnel with diatomaceous        earth.    -   3. The filtrate was ion exchanged with 50 ml ion exchange resin        per liter filtrate at 45° C. for 30 minutes.    -   4. The ion exchange resin was drained on nylon cloth.    -   5. The ion exchanged filtrate was precipitated in three volumes        of 80% iso propyl alcohol.    -   6. The precipitate was washed once with 60% iso propyl alcohol        and dried at 65° C. for 24 hours.

Analysis of Samples from Examples

Examples 1-10 deal with laboratory experiments whereas Examples 11-14deal with experiments in pilot plant and Examples 15-18 deal withexperiments in pilot plan on pectin and carrageenan waste materials.

Example 1 Effects of Alcohol Strength

In the first set of experiments, peel dry matter, pectin yield, residualsugar concentration in the peel DE, and pectin molecular weight M_(w)were measured after one wash and one pressing under different conditionsand the data is shown below in Table 1.

TABLE 1 Dry Matter, Sugar Concentration, Pectin Yield, DE and MolecularWeight of Washed and Pressed Peel. Wash Dry Matter Residual M_(W) SampleWetting No. Time No. Of Pressed in the Peel Pectin KDalton No.Composition Wash Min Press peel % Sugar % Yield % DE % of Pectin 9 96%EtOH 1 15 1 20.0 25.1 17.0 74.3 240 10 70% EtOH 1 15 1 17.2 21.8 17.472.1 218 11 50% EtOH 1 15 1 14.5 14.2 71.7 216 0 No wash, 13.0 44.7 nopress 1 No wash 1 17.2 40.3 7 Water 1 15 1 11.6 11.4 73.2 189 8 Water, 115 1 11.4 24.3 13.9 71.7 216 pH = 4

According to the data in Table 1, pectin yield increased with increasingalcohol concentration in the wetting composition. This indicates that analcohol concentration of at least 70% resulted in significantly lessloss of pectin in the wash.

Table 1 also shows that the DE increased marginally with the alcoholconcentration, and the molecular weight increased as the alcoholconcentration increases from 70% to 96%. This indicates that the alcoholconcentration was relevant to the loss of pectin during the washing, andthat an alcohol concentration of at least about 70% to 96% may bedesirable for some embodiments. In addition, Table 1 shows that withoutwashing and pressing, peel dry matter is about 13%. With washing inplain water and with water at pH 4, dry matter is reduced to about 11%.When washing in alcohol followed by one pressing, the peel dry matterincreases with the alcohol concentration up to about 20% when using 96%alcohol. In these experiments, washing in plain water and in waterhaving pH 4 provided for about the same sugar concentration in the peelas washing with alcohol does. In both cases, the sugar concentration wasreduced to about 22-25%.

Thus, these first experiments show that particularly the pectin yield isincreased through washing with alcohol, and peel dry matter issubstantially increased whereas residual sugar is marginally decreasedcompared to a regular washing with water.

Example 2 Effect of Number of Alcohol Wash

In this set of experiments, the number of alcohol washing steps wasinvestigated.

TABLE 2 Dry Matter and Residual Sugar in Peel Being Washed DifferentNumber of Times. Sugar Wash Dry Matter Residual Sample Wetting No. TimeNo. of Pressed Sugar in No. Composition wash Min. press Peel % the Peel% 9 96% EtOH 1 15 1 20.0 25.1 12 96% EtOH 2 15 1 24.2 18.6 13 96% EtOH 315 1 24.2 19.0 14 96% EtOH 4 15 1 21.5 17.9

According to the data in Table 2, with 2-3 washes in 96% alcohol, thepeel dry matter increased by about 20% after one pressing. 2-4 washingsin 96% alcohol reduced the sugar concentration in the peel to about 18%or about 30% compared to washing once in 96% alcohol. Thus, 2-4 washingsprovided the highest dry matter and the lowest residual sugarconcentration in the washed peel.

Example 3 Effect of Washing Time

Next, the washing time was investigated. Peel dry matter and residualsugar was recorded for peel being washing for different times in 96%alcohol followed by one pressing.

TABLE 3 Dry Matter and Residual Sugar in Peel Washed for DifferentTimes. Wash Sugar Residual Sample Wetting No. Time Dry Matter Of Sugarin Peel No. Composition Wash Min. Pressed Peel % % 4 96% EtOH 1 15 23.525.1 5 96% EtOH 1 30 23.0 20.5

According to the data in Table 3, with one pressing, peel dry matter wasunchanged when washing time was increased from 15 minutes to 30 minutesand residual sugar was decreased with increasing washing time. Thus, thedata in Table 1 indicates that washing for about 30 minutes provided forhigh peel dry matter and low residual sugar in the peel.

Example 4 Effect of Washing Temperature

In the next experiments, peel was washed at different temperatures in70% alcohol. After each wash of 60 minutes, the washed peel was pressedthree times.

TABLE 4 Effects of Washing Temperature Residual Biomass Wash Dry MatterSugar Sample Slurry Liquid No. Time No of of Pressed in Peel Pectin % MwKDalton No. Temp. ° C. Wash min Press Peel % Sugar % Yield % DE ofPectin 30 24 4 60 3 25.3 6.5 19.3 75.4 217 31 50 4 60 3 24.1 4.0 20.378.9 200

According to the data in Table 4, higher biomass slurry liquidtemperature provided for a lower peel dry matter, and the peel drymatter was reduced by about 5% when washing temperature was increasedfrom 24 to 50° C. In addition, with increasing washing temperature, thesugar concentration in the washed peel was reduced. The sugar level wasreduced by about 40% when the washing temperature was increased from 24to 50° C. The data in Table 4 also shows that the pectin yield wasincreased by about 5% when washing temperature was increased from 24 to50° C., which may be a result of lower residual sugar. Furthermore, theDE of the resulting pectin appears to have been increased from about 75%to about 79% when the washing temperature was increased from 24 to 50°C. and, when the washing temperature was increased from 24 to 50° C.,the molecular weight appears to have been reduced by about 8%. Thus,high washing temperature may favor a lower residual sugar level in thepeel, a higher pectin yield and a higher DE, whereas low washingtemperature may favor a higher molecular weight.

Example 5 Effect of pH in Wash

In the next set of experiments, fresh peel was washed in alcohol atdifferent pH. The peel was washed four times and each time for one hour.After each wash, the washed peel was pressed three times.

TABLE 5 Effect of Wash at Different pH pH in Liquid Component Wash DryMatter Residual Sample of Biomass No. Time No. of Pressed Sugar % Pectin% DE of Mw KDalton No. Slurry wash min press Peel % in Pectin Yield %Pectin of Pectin 26 1 4 60 3 24.6 5.0 16.5 75.8 238 27 4 4 60 3 25.5 6.117.8 75.7 252 28 7 4 60 3 24.8 5.8 17.0 75.7 259 29 10 4 60 3 25.0 6.915.2 68.4 180

The data in Table 5 shows that the peel dry matter was constantirrespective of the pH in the liquid component of the biomass slurry,whereas it appears that the sugar concentration in the washed peelincrease with increasing pH of the liquid component of the biomassslurry. The sugar level was reduced by about 30% when the pH of theliquid component of the biomass slurry was reduced from pH 10 to pH 1.According to the data in Table 5, the pectin reached a maximum whenwashing was conducted in the pH range from about 4 to about 7. Thepectin yield was about 15% lower at pH 10 than at pH 4. In the pH rangefrom about 1 to about 7, DE was constant. However, as the pH was furtherincreased to 10, the DE dropped by about 10%. The molecular weight ofthe resulting pectin stayed substantially constant after wash in the pHrange from about 1 to about 7. However, as pH was further increased to10, the molecular weight dropped about 30%. Thus, the data in Table 5indicates that low pH favors low residual sugar in the peel, high pectinyield, high DE and high molecular weight of pectin.

Example 6 Effect of Number of Pressings

In the first set of these experiments, fresh peel was washed three timesone hour in alcohol. After each washing, the washed peel was pressedonce or twice. In the second set of these experiments, fresh peel waswashed four times in alcohol and after each wash pressed once, twice andthrice.

TABLE 6 Effect of the Number of Pressings Wash Dry Matter ResidualSample Wetting No. Time No. of Pressed Sugar in Pectin % DE Mw KDaltonNo. Comp. Wash min Press Peel % Pectin % Yield % of Pectin of Pectin 1870% 3 60 1 18.8 6.8 21.6 71.2 237 EtOH 19 70% 3 60 2 23.3 5.6 20.4 70.9204 EtOH 20 96% 3 60 1 18.4 13.0 22.8 73.9 226 EtOH 21 96% 3 60 2 20.0115 19.7 73.1 222 EtOH 22 70% 4 60 1 19.2 6.2 21.9 75.1 314 EtOH 23 70%4 60 2 21.1 4.3 19.0 72.0 253 EtOH 24 70% 4 60 3 23.2 3.6 21.1 71.8 261EtOH

According to the data in Table 6, pressing twice increased the peel drymatter. However, it appears that twice pressing in 70% alcohol providedfor the strongest increase in peel dry matter. Compared to a control inwhich peel was washed once and pressed once, three times washing with70% ethanol and pressing twice after each wash increased dry matter fromabout 13% to about 24%, almost a doubling of the dry matter. The numberof pressing steps did not change the sugar level much. However, 70%ethanol appears to have provided for the lowest sugar concentration inthe washed and pressed peel. The data in Table 6 indicates that pressingtwice results in a slight decrease in pectin yield. The DE of theresulting pectin was hardly affected by the number of pressings. Thisdata may indicate a tendency for washing in 96% ethanol to provide forslightly higher DE. In addition, the data in Table 6 seems to indicate atendency for the molecular weight to drop as the number of pressingsincrease. This tendency was more pronounced for washing in 70% alcoholthan in 96% alcohol.

Thus, the first set of experiments indicated that the number ofpressings favors a higher peel dry matter and to some extent the amountof residual sugar. However, a lowered strength alcohol appears to havehad a stronger effect. On the other hand, the number of pressings seemsto have favored a marginal lower DE and molecular weight.

The data in Tables 5 and 6 show that there does not seem to be a majordifference in peel dry matter whether the peel is washed three or fourtimes and pressed two or three times. However, the lowest concentrationof sugar in the washed peel was accomplished using four washes and threepressings after each wash. Furthermore, the data in Tables 5 and 6 showthe number of washing and number of pressings had no major effect onpectin yield, a tendency for slightly lower yield as the number ofpressings was increased, and the DE of the resulting pectin stayedunchanged as the number of washings and the number of pressings wasincreased.

The data in Table 6 shows that four washings provided higher molecularweight and pressing once provided higher molecular weight. Thus, thissecond set of experiments indicate that more washing and higher numberof pressings favor a lower residual sugar level in the peel, whereasmore washing and low number of pressings favor a higher molecular weightof the resulting pectin. The data in Tables 5 and 6 also indicate thatthe peel dry matter, the pectin yield and the DE of the resulting pectinappear to be unaffected by more washing steps and a higher number ofpressings.

Example 7 Effect of Pressing Time

In these experiments the number of alcohol washings was four, and aftereach pressing, the pressing time was set to various times ranging from 0seconds and up to 600 seconds.

TABLE 7 Effect of Pressing Time Wash Press Dry Matter Residual SampleWetting No. Time No. Time Of Pressed Sugar % Pectin % DE Mw KDalton No.Comp. Wash Min Press Sec. Peel % in Pectin Yield % of Pectin of Pectin43 70% 4 60 3 0 25.6 6.4 18.2 76.8 206 IPA 0 0 44 70% 4 60 1 60 24.3 8.020.2 74.9 251 IPA 45 70% 4 60 2 60 27.7 7.2 20.2 73.4 245 IPA 60 46 70%4 60 1 180 25.9 7.5 18.3 76.7 262 IPA 47 70% 4 60 2 180 34.7 7.2 17.976.9 215 IPA 600 54 70% 4 60 3 180 37.7 5.1 18.5 76.0 203 IPA 600 600 5270% 4 60 3 180 35.0 5.0 17.7 77.1 269 EtOH 600 600

The data in Table 7 shows that when peel was pressed once, but with aholding time of 60 seconds, the dry matter was about the same as forpeel being pressed three times, but without holding time. As the holdingtime was increased, the peel dry matter increased, and the peel drymatter using a triple pressing with holding times 180 seconds, 600seconds and 600 seconds, respectively, provided for the highest peel drymatter, about 37%, which was about three times the value of peel washedin water and pressed once without holding time. With ethanol, the drymatter of the peel was almost as high as with IPA.

The data featured in Table 7 indicates that the sugar level wasgenerally low, but there seemed to be an advantage in pressing withtotal holding time of about 20 minutes the same result was observed withethanol.

According to the data in Table 7, both pectin yield and DE of theresulting pectin appeared to be independent of the pressing time. In theExamples featured in Table 7 with IPA, molecular weight appeared to behighest when pressing times were no more than about 180 seconds. As thetotal pressing time increased, the molecular weight decreased. However,with ethanol, the molecular weight remained high even at the long totalpressing times.

Thus, the data in Table 7 indicates that pressing time favored high peeldry matter and low residual sugar, whereas pressing time did notinfluence pectin yield and DE of the resulting pectin.

In the Examples featured in Table 7, there appeared to be a tendency oflower molecular weight of the resulting pectin when washing was donewith IPA and pressing time exceeded 180 seconds. However, with ethanol,high molecular weight seemed to be favored by longer pressing times.

Example 8 Effect of Pressure During Pressing

In order to indicate the effect of the pressure used during pressing,two tests were made. One with a load cell allowing for a pressure of 25kg. and a load cell allowing for a pressure of 50 kg.

TABLE 8 Effect of Pressure During Pressing Load Wash Pressing Dry MatterResidual Pectin Sample Wett. Cell No. Time No. Time Of Pressed Sugar %Yield % % DE No. Comp. Kg Wash Min Press sec Peel % in Pectin of Pectinof Pectin 57 70% 25 4 60 3 60 32.2 3.9 20.7 74.6 EtOH 300 180 58 70% 504 60 3 60 34.1 4.3 18.4 70.7 EtOH 300 180

In the Examples featured in Table 8, increasing pressure provided for atbest a marginal increase in peel dry matter, whereas it seems thathigher pressure led to somewhat higher sugar concentration. In addition,higher pressure seemed to lead to a somewhat lower pectin yield.However, the yield was comparable with previous findings. A slightdecrease in DE was observed at high pressure, but both DE values werewithin the previous findings.

Example 9 Effect of Alcohol Type

In this set of experiments, the difference between IPA and ethanol wasfurther investigated. In the case of IPA, four independent tests wereconducted.

TABLE 9 Effect of Alcohol Type Wash Dry Matter Pectin Sample Wetting No.Time No. Of Pressed Sugar Yield % Mw KDalton No. Comp. Wash Min PressPeel % % % DE of Pectin 39 70% IPA 4 60 3 28.3 12.4 17.8 70.9 185 40 70%IPA 4 60 3 26.4 6.7 18.3 73.9 196 41 70% IPA 4 60 3 26.5 6.9 17.7 75.5205 42 70% IPA 4 60 3 26.7 6.2 19.7 75.5 195 43 70% IPA 4 60 3 25.6 6.418.2 76.8 206 IPA 26.7 7.7 18.3 74.5 197 average 30 70% 4 60 3 25.3 6.519.3 75.4 217 EtOH

In the data featured in Table 9, when using IPA, the peel dry matterincreased by about 5% compared to ethanol. However, sugar concentrationwas about 15% lower when using ethanol compared to IPA. Ethanol appearedto provide for a slightly higher yield, about 5% and a marginally higherDE. Ethanol appeared to provide for higher molecular weight—about 10%.Thus, in Example 9, ethanol favored higher pectin yield and higherpectin molecular weight, whereas IPA favored higher peel dry matter andlower residual sugar.

Example 10 Comparison of Lemon and Orange

A comparison of the various treatments performed on lemon and orangepeel was made.

TABLE 10 Comparison of Lemon and Orange Wash Dry Matter Reduced SampleWetting No. Time No. Of Pressed Sugar % Pectin % DE of No. Peel Comp.Wash Min Press Peel % in Pectin Yield % Pectin 1 Lemon No wash 1 17.240.3 9.5 73.7 17 Lemon Water - 2 15 1 10.1 19.8 18.8 72.5 pH = 4 24Lemon 70% EtOH 4 60 3 23.2 3.6 21.2 71.8 49 Orange No wash 0 1 20.9 40.47.5 73.0 50 Orange Water - 2 15 1 10.7 23.1 14.9 73.6 pH = 4 51 Orange70% EtOH 4 60 3 24.0 6.2 18.9 74.8

In the data featured in Table 10, the dry matter was reduced markedlywhen washing was conducted at pH 4, washing in 70% ethanol and pressingthree times after each wash increased the dry matter, the dry matterbecame higher in orange compared with lemon, washing and pressinggreatly reduced sugar concentration, and the ethanol wash and pressingwas very effective. In addition, the pectin yield increased with washingand was highest for the peel having been washed with ethanol, however,the DE was unaffected.

The foregoing laboratory Scale-Examples indicated:

With respect to alcohol strength, the pectin yield was increased whenthe alcohol strength was 70% by weight of the wetting composition orhigher. Peel dry matter was substantially increased and residual sugarwas marginally decreased compared to washing with water. The number ofwashing steps had a substantial effect, and 2-4 washing steps appearedto be the optimal number of washing steps to provide for the highest drymatter in the peel and the lowest residual sugar concentration in thewashed peel. Washing time also played a role, and the optimum washingtime appeared to be about 30 minutes to provide for high peel dry matterand low residual sugar level in the peel. High washing temperatureseemed to favor a lower residual sugar level in the peel, a higherpectin yield and a higher DE of the resulting pectin. However, lowwashing temperature appeared to favor a higher molecular weight of theresulting pectin. Low pH favored low residual sugar in the peel, highpectin yield, high DE of the resulting pectin and high molecular weightof the resulting pectin. The number of pressings after wash seemed tofavor a higher peel dry matter and to a lesser extent the residual sugarlevel. However, when combining number of pressing with number of washingsteps, the residual sugar was reduced while the peel dry matter stayedsubstantially constant. The pressing time favored high peel dry matterand low residual sugar, but did not influence the pectin yield or the DEof the resulting pectin. Using a three step washing in 70% alcoholcombined with a triple pressing with holding times of 180+600+600seconds, the peel dry matter was increased three fold to 37%. Thepressure during pressing appeared to have no substantial impact and thesame appeared to be true when the volume of wash liquid was doubled.With respect to the alcohol type, ethanol appeared to favor marginallyhigher pectin yield and marginally higher pectin molecular weight,whereas isopropanol favored marginally higher peel dry matter and lowerresidual sugar. Thus, ethanol and isopropanol could be usedinterchangeably. With respect to pectin starting material, lemon andorange behaved about the same. According to these laboratoryexperiments, a particularly desirable embodiment appears to be a processin which fresh peel is washed three times in 70% alcohol at roomtemperature, each washing step is conducted for 30 minutes and aftereach wash, the washed peel is pressed three times at 4-8 bar, eachpressing time being maintained for about 200-600 seconds.

The next examples were made to validate the laboratory findings in pilotplant scale and to evaluate the concept of using a countercurrentalcohol wash with one single pressing step after the washing.

Example 12 Consecutive Washing and Pressing of Fresh Peel in Pilot Plant

In the Example 12, freshly juiced orange peel was used as the startingmaterial and for pressing, a screw type press was used.

The results from the washing and pressing experiments are listed inTable 11. After each pressing, fresh 80% IPA was added for the followingwash.

Example 11 Results of Washing with IPA Followed by Pressing

IPA IPA Centrifuged Peel Dry % IPA Peel Spent Added Impurities PectinSample Comment Matter % Density Kg Liter Liter In IPA % Yield % 1151-Fresh 22.4 117 129.5 104-1 peel 1151- Fresh 22.3 104-2 peel + IPA1151- 1. press 23.8 52 66 135 121.2 4 13.3 104-3 1151- 2. press 35.6 6825.7 170 35 2 104-4 1151- 3. press 50.5 15.6 50 30 3 34.2 104-5 1151- 4.press 57.6 78 11.2 45 30 4 36.4 104-6 1151- 5. press 59.5 80 8.7 35 30 431.9 104-7 1151- 6. press 56.0 80 7.5 35 5 104-8 1151- 7. press 50.3 808.0 30 5 104-9

Table 12 shows the results from laboratory analysis. As a measure formolecular weight, the intrinsic viscosity was chosen.

TABLE 12 Laboratory Analysis Residual Pectin Clarity Clarity Sam- Sugarin Pectin Pectin IV Cold Warm pH ple Peel % DE % GA % dl/g % T % T 1%1151- 33.3 62.5 81.6 4.836 67.4 78.0 3.15 104-3 1151- 21.1 104-4 1151-13.9 63.8 81.9 5.094 85.1 87.0 3.46 104-5 1151- 11.8 65.0 81.3 5.12435.9 82.4 3.62 104-6 1151- 10.4 63.4 79.9 4.926 42.2 81.9 3.33 104-71151- 9.6 104-8 1151- 9.4 104-9

The data featured in Tables 11 and 12 indicate that washing and pressing4-6 times increased the peel dry matter to above 50% by weight of thepeel, and at those washings and pressings, the IPA concentration in thespent IPA was constant at about 80% by weight of the wettingcomposition. In addition, the pectin yield was increased to above 30%.In addition, after about 5 pressings, the residual sugar level in thepressed peel fell to about 10%. Furthermore, in data featured in Tables11 and 12, the DE, GA and IV (molecular weight) of the resulting pectinproducts were fairly constant irrespective of the number of washings andpressings. In addition, these are all within normal range, which mayindicate that the high pectin yield is not caused by impurities.However, the clarity of cold solution of the resulting pectin productsappeared to be decreasing as the number of washings and pressings wereincreased, whereas the clarity of warm pectin solutions remained high.

This could be due to the increased maceration of the peel with increasednumber of pressings. Still, the impurities appeared to be soluble hot.This could have indicated that the low clarity might be a result of thefruit used in the examples being waxed.

Thus, the Examples featured in Tables 11 and 12 showed that when using ascrew type press, substantially higher peel dry matter was achievablecompared to the hydraulic type press used in the laboratory experiments.These examples also verified pressing time as an important factor. Thescrew type press used in these examples ran with about 20 rpm, whichcorresponded to a run through time of about 10-15 minutes.

Example 11 Four Steps Countercurrent Wash with Isopropanol in PilotPlant

The results from washing of peel are listed in Table 13.

TABLE 13 Washing Time and Density of IPA Washing Density of Time IPAMinutes g/ml 5 0.880 10 0.890 15 0.895 20 0.895

The results from washing and pressing are listed in Table 14.

TABLE 14 Results of Countercurrent Wash and Pressing Peel IPA IPA IPAPeel Dry Pectin Sample Kg. Kg. Density % GC % Matter % Yield %1151-105-0 20.1 2.3 1151-105-A1 21.2 27.0 54 46.12 18.5 1151-105-A2 18.725.2 70 58.08 18.0 1151-105-A3 18.2 23.8 78 63.34 20.6 1151-105-A4 18.121.7 79 60.77 21.2 1151-105-A- 3.9 31.7 78 60.76 39.4 28.8 press1151-105-B1 20.5 23.0 42 36.63 17.4 1151-105-B2 19.9 19.5 62 51.94 27.61151-105-B3 18.8 32.2 70 50.99 27.6 1151-105-B4 18.4 21.6 77 63.95 30.01151-105-B- 2.0 24.0 78 63.95 54.4 31.2 press 1151-105-C1 20.0 21.2 3635.08 21.3 1151-105-C2 18.1 32.6 70 48.09 27.8 1151-105-C3 17.4 35.4 7455.29 24.9 1151-105-C4 15.9 18.1 78 60.08 26.4 1151-105-C- 3.6 34.8 7860.08 46.8 29.3 press 1151-105-D1 21.2 32.0 42 35.28 27.2 1151-105-D219.9 37.3 62 45.21 25.5 1151-105-D3 19.1 34.5 70 51.80 27.4 1151-105-D418.5 21.4 78 58.61 29.6 1151-105-D- 4.4 40.8 76 58.47 46.2 28.3 press1151-105-E1 20.4 33.9 42 33.38 24.5 1151-105-E2 19.2 33.8 58 43.68 26.91151-105-E3 17.8 35.5 70 53.15 23.9 1151-105-E4 17.3 32.0 78 62.89 26.41151-105E- 3.8 36.0 76 62.80 48.6 28.1 press

Table 15 lists the laboratory analysis of the resulting pectin productsfrom each step in the countercurrent wash and pressing.

TABLE 15 Analysis of Resulting Pectin Products Clarity Clarity ResidualMw IV Cold Hot CS + Ca²⁺ CS − Ca²⁺ Pectin Sugar % KDalton dl/g DE % GA %% T % T pH cP cP 1151- 16.05 301 5.458 60.8 81.3 32.0 30.1 3.13 22.911.8 105-0 1151- 15.25 303 5.184 65.8 80.2 14.4 15.3 3.16 105-A 1151-14.55 291 5.177 66.1 80.0 13.6 13.3 3.13 105-B 1151- 15.24 255 4.35965.4 79.6 13.2 13.2 3.17 105-C 1151- 13.08 288 5.270 63.5 83.1 87.3 89.63.36 105-D 1151- 16.05 268 4.917 65.5 81.7 15.4 16.0 3.08 53.5 13.5105-E

The theoretical mass balance is listed in Table 16.

TABLE 16 Theorectical Mass Balance According to the E-Series IPA IPAPeel Peel Wash Spent After Step Kg Kg Kg Kg Start 20.0 20.0 First wash20.0 40.6 40.2 20.4 Second wash 20.4 39.4 40.6 19.2 Third wash 19.2 38.039.4 17.8 Fourth wash 17.8 24.0 38.0 17.3 Press 17.3 13.5 3.8

A mass balance according to the E-series:

TABLE 17 Mass Balance of Countercurrent Wash Peel IPA IPA IPA IPA PeelDry Pectin Peel Wash Wash Spent Spent After Matter Yield Step Kg Kg % Kg% Kg % % Start 20.0 20.0 20.1 2.3 First 20.0 37.3 45.21 33.9 33.38 20.424.5 wash Second 20.4 34.5 51.80 33.8 43.68 19.2 26.9 wash Third 19.240.8 58.61 35.5 53.15 17.8 23.9 wash Fourth 17.8 24.0 80.00 36.0 62.8017.3 26.4 wash Press 17.3 3.8 48.6 28,.1

Similarly, a mass balance according to the D-series:

TABLE 18 Mass Balance of Countercurrent Wash IPA IPA Wetting Wetting IPAIPA Peel Peel Dry Pectin Peel Comp. Comp. Spent Spent After Matter YieldStep Kg Kg % Kg % Kg % % Start 20.0 20.0 20.1 2.3 First wash 20.0 32.648.01 32.0 35.28 21.2 27.2 Second wash 21.2 35.4 55.29 37.3 45.21 19.925.5 Third wash 19.9 34.8 60.08 35.4 51.80 19.1 27.4 Fourth wash 19.124.0 80.00 40.8 58.47 18.5 29.6 Press 18.5 4.4 46.2 28.3

FIG. 1 shows a mass balance of series E and shows that there is a goodcorrelation between the IPA concentration in the spent liquid componentfrom the biomass slurry and the IPA concentration in the prior incomingIPA wetting composition. Also, the amounts of liquid component from thebiomass slurry being used in the prior washing step correlate reasonablywell with the spent liquid component from the subsequent washing step.However, the actual data did not equal the theoretical values. This mayreflect the fact that these were some losses during the process, so thescale may have been too small. Thus, the countercurrent scheme used inthese experiments did provide for a reasonable steady state system inwhich the countercurrent wash results in about 4 kg peel with a drymatter of about 28% by weight of the peel and a spent amount of alcoholfor distillation amounting to about 35 kg having an IPA concentration ofabout 34%. Energy wise, the spent IPA to be distilled comes from the IPAin the pressed peel and the spent IPA from the first wash. Afterpressing, 3.8 kg wet peel is produced, which correspond to 1.846 kg drypeel and 1.954 kg IPA. The IPA has a strength of 62.8% by weight of thewetting composition which translates into 1.227 kg IPA. Theoretically,spent IPA in the first wash is the IPA being led into wash No. 4, namely24 kg with a strength of 80% or 19.2 kg IPA minus the IPA leaving withthe pressed peel. Thus, the amount of IPA to be distilled is 17.973 kg.Theoretically, the amount of IPA leaving from wash No. 1 is the amountIPA coming from Wash. No. 2 minus the IPA leaving with the washed peel.This amounts to 40.2 kg, which translates into this IPA having astrength 45%, which is somewhat higher than the actual measurement of33.4%. In order to calculate the energy consumption, one has to make theassumption that the IPA going into wash No. 4 is not 24 kg. but only 15kg. In this case, the spent IPA in wash No. 1 becomes 31.2 kg with astrength of 34.5%, which is close to the actual measurements.

The following tables show the energy consumption of an alcohol washingprocess in accordance with an embodiment of this invention and theconventional drying process.

TABLE 19 Energy Consumption of Alcohol Washing Process Alcohol ProcessMT/MT Peel Wet Peel 9 Water 0 Effluent 8 Steam 2.52 Steam cost R$/MT 45Energy cost R$/MT Peel 113 Energy cost US$/MT Peel 49 Pectin Yield 25%Pectin MT/MT Peel 0.250 Specific energy cost R$/MT Pectin 453 Specificenergy cost US$/MT Pectin 197

TABLE 20 Energy Consumption of Conventional Drying Process ConventionalDrying Process MT/MT NM3/MT Peel Peel Wet Peel 9 Water 23 Effluent 32Nat Gas 524 Nat Gas cost R$/NM3 1.45 Energy cost R$/MT Peel 760 Energycost US$/MT Peel 330 Pectin Yield 25% Pectin MT/MT Peel 0.250 Specificenergy cost R$/MT Pectin 3040 Specific energy cost US$/MT Pectin 1322

TABLE 21 Savings When Using Alcohol Washing Process Savings MT/MT PeelWet Peel 0 Water 23 Effluent 24 Energy cost R$/MT Peel 647 Energy costUS$/MT Peel 281 Specific energy cost R$/MT Pectin 2587 Specific energycost US$/MT Pectin 1125

As shown in Tables 19-21, per 1 mT dry peel, an alcohol washing andpressing process according to an embodiment of this invention reducesthe energy cost by about 280 USD per mT dry peel. In addition, thealcohol process in accordance with an embodiment of this invention saveson water consumption and effluent and reduces the amount of CO₂ emittedby about 1 mT CO₂ per 1 mT produced dry peel. With respect to the pectinquality, there seemed to be a tendency of higher DE in pectin havingbeen subjected to the alcohol washing process. As previously observed,the clarity appeared to suffer during the alcohol washing process. Thus,since this work applies only one pressing, the amount of fines wassubstantially less than what was observed with a process involvingconsecutive washing and pressing. Without being bound of theory, it isexpected that the lack of clarity was caused by the fact that thestarting material was peel from fresh oranges destined to be eaten asfresh fruit. Such fruit is conventionally waxed, and it is suspectedthat the wax is the cause of lower clarity. In addition, galacturonicacid was high, which indicated a pure pectin, and the washing withalcohol removed substantial amounts of sugar from the fresh peel.

Example 13 Four Steps Countercurrent Wash with Ethanol in Pilot Plant

A countercurrent experiment was performed with ethanol instead ofisopropanol.

Table 22 shows the data from the washing and pressing scheme.

TABLE 22 Results of Countercurrent Wash and Pressing. EtOH EtOH Peel DryPectin Peel EtOH Density GC Matter Yield Sample Kg Kg % % % % 1151-106-022.6 31.2 1151-106-A1 22.4 28.1 46 27.0 1151-106-A2 21.6 26.5 64 56.3828.9 1151-106-A3 20.9 25.1 70 66.09 26.9 1151-106-A4 18.7 25.2 64.6525.7 1151-106-A-press 5.5 37.5 70 66.11 51.6 31.2 1151-106-B1 23.2 28.848 50.38 29.0 1151-106-B2 22.8 24.6 60 55.94 33.6 1151-106-B3 21.7 37.666 58.41 27.3 1151-106-B4 21.3 263 72 68.51 24.2 1151-106-B-press 5.940.0 70 63.39 46.8 31.1 1151-106-C1 25.2 18.8 24 34.35 30.5 1151-106-C223.3 39.4 24 48.97 28.0 1151-106-C3 22.1 38.5 58 58.47 25.7 1151-106-C420.9 28.6 68 61.79 27.1 1151-106-C-press 6.4 53.6 66 60.21 45.4 32.01151-106-D1 25.5 32.5 32 34.60 24.8 1151-106-D2 24.9 39.4 56 49.72 25.21151-106-D3 22.8 43.5 56.18 24.7 1151-106-D4 21.7 25.4 70 61.74 26.11151-106-D-press 4.6 40.8 68 60.20 45.0 31.9 1151-106-E1 25.3 33.5 3437.41 25.5 1151-106-E2 24.4 43.5 54 47.69 27.7 1151-106-E3 22.0 41.1 6455.55 29.4 1151-106-E4 21.2 21.8 70 61.15 24.2 1151-106-E-press 4.5 37.568 60.58 60.3 34.4 Note: Extraction made on dried peel.

Table 23 lists the laboratory analysis of the resulting pectin productsfrom each step in the countercurrent wash and pressing.

TABLE 23 Analysis of Resulting Pectin Products Clarity Clarity ResidualMw IV DE GA Cold Hot CS + Ca²⁺ CS − Ca²⁺ Pectin Sugar % KDalton dl/g % %% T % T pH cP cP 1151-106-0 39.7 267 5.262 66.4 80.7 71.4 70.7 3.27 65.514.6 1151-106-A 7.9 306 5.877 68.6 79.4 73.2 89.9 3.46 1151-106-B 9.5350 6.143 67.7 78.8 72.4 89.5 3.56 1151-106-C 10.6 346 6.016 67.5 79.877.7 90.4 3.39 1151-106-D 9.8 243 4.555 67.3 80.5 47.4 86.0 3.491151-106-E 9.3 271 5.769 69.1 82.7 86,.1 87.3 3.42 34.0 16.6

The theoretical mass balance is listed in Table 24.

TABLE 24 Theoretical Mass Balance According to the E-series EtOH Wett.EtOH Peel Peel Comp. Spent After Step Kg Kg Kg Kg Start 20.0 22.4 Firstwash 20.0 44.8 33.5 25.3 Second wash 25.3 43.9 44.8 24.4 Third wash 24.441.5 43.9 22.0 Fourth wash 22.0 24.0 24.8 21.2 Press 21.2 16.7 4.5

A Mass balance according to the E-series:

TABLE 25 Mass Balance of Countercurrent Wash EtOH Peel Wett. EtOH EtOHEtOH Peel Dry Pectin Peel Comp. Wash Spent Spent After Matter Yield StepKg Kg % Kg % Kg % % Start 20.0 20.0 22.6 31.3 First 20.0 43.5 47.69 33.537.41 25.3 25.5 wash Second 25.3 41.1 55.55 43.5 47.69 24.4 27.7 washThird 24.4 37.5 60.58 41.1 55.55 22.0 29.4 wash Fourth 22.0 24.0 80.0015.7 61.15 21.2 24.2 wash Press 21.2 21.8 60.58 4.50 60.3 34.4

FIG. 2 shows the mass balance according to the E-series and there was apretty good correlation between the theoretical mass balance and theactual one.

From an energy saving point of view, the cost saving is the same as wasfound in the experiments with iso propanol, which also means that theemission of CO₂ is reduced to the same level as washing with isopropanol. With respect to the quality of the resulting pectin, it is asa minimum on par with the pectin quality of the resulting pectin fromthe non-alcohol washed peel. The ethanol wash seemed to have providedfor a pectin product with a higher molecular weight as measured byintrinsic viscosity, a higher DE, and a higher pectin purity as measuredby the galacturonic acid. Additionally, washing with ethanol increasesthe clarity of the resulting pectin's clarity in solution. Further, thecalcium sensitivity of the pectin appears to be somewhat reduced throughwashing with ethanol, however, this may very well be within experimentalerror.

Example 14 Two Steps Countercurrent Wash with Ethanol in Pilot Plant

The Examples 12 and 13 show that washing with alcohol and subsequentpressing once provides for a substantial energy saving in the followingdrying of the washed and pressed polymer containing material. They alsoshow that the resulting quality of the polymer when extracted from thewashed, pressed and dried material remains at least on par with thepolymer resulting from extraction of the same material as is, i.e. thematerial not being washed and pressed.

Table 26 shows the result from the pilot plant experiment with a twostep countercurrent wash followed by a pressing.

TABLE 26 Results of Countercurrent Wash and Pressing EtOH Peel DryPectin Peel EtOH Density Matter Yield Sample Kg Kg % % % 1151-109-0 20.018.3 1151-109-A3 22.0 20.8 48 27.2 1151-109-A4 21.7 25.1 66 27.41151-109-A-press 4.8 39.3 62 55.0 33.9 1151-109-B3 21.9 35.0 44 54.61151-109-B4 20.3 26.2 65 26.6 1151-109-B-press 5.1 38.9 75 57.6 32.21151-109-C3 21.6 32.8 39 26.0 1151-109-C4 18.7 26.0 62 27.31151-109-C-press 4.9 38.0 61 58.2 33.8

According to the Examples 12-14, the peel dry matter after pressing wasabout 60%, which was the same as the peel dry matter using a four stepwashing scheme, so it is was possible to achieve the energy savingsusing a two step countercurrent washing followed by pressing once. Thus,Examples 12-14 showed that using a countercurrent washing schemeconsisting of 2-4 washing steps provided for high pectin yield even withalcohol concentrations in the washings in the range from about 45% toabout 80%. In addition, such countercurrent washing scheme provided fora pectin product which was at least on par with the pectin product beingextracted from peel, which has not undergone such countercurrent wash.

Example 15 Four Steps Countercurrent Wash of Pectin Waste withIsopropanol in Pilot Plant

Another example of a polymer containing material is the waste materialfrom the pectin production. Such waste is traditionally used for cattlefeed, and this example was done to evaluate the alcohol washing andpressing process to establish if this process would lead to a wasteproduct, which has enough dry matter to be combustible. Results from theexperiment are listed in Table 27.

TABLE 27 Results from Washing and Pressing Pectin Waste Material IPAWaste Dry Sample Waste Kg IPA Kg Density % Matter % 1151-105-0 20.0 16.81151-105-F1 9.5 42.1 30 24.4 1151-105-F2 9.1 36.2 50 33.8 1151-105-F37.7 34.1 60 33.9 1151-105-F4 8.0 33.2 70 28.9 1151-105-F-press 4.3 25578 51.5

Thus, when using a four step countercurrent wash with isopropanolfollowed by a single pressing, a dry matter of the waste of about 50%was achieved. This makes the waste combustible with an assumedcombustion value about the same as wood with about 50% dry matter.

-   Combustion value of pectin waste: 8 GJ/ton-   Combustion value of natural gas: 39 GJ/1000 m³

Thus, by using the such washed and pressed pectin waste, about 20%natural gas can be saved with a following reduction in CO₂ emission.

Example 16 Consecutive Washing and Pressing with Isopropanol of PectinWaste in Pilot Plant

In order to establish if the same dry matter of pectin waste would beprovided through consecutive washing and pressing, pectin waste materialwas washed in 80% isopropanol for 20 minutes and subsequently pressed onscrew press at a counter pressure of 4 bar.

The results are listed in Table 28.

TABLE 28 Dry Matter of Washed and Pressed Pectin Waste Sample CommentWaste Dry Matter % H-41 - Pectin Fresh waste 12.6 H-41 - Pectin 1. washand press 50.4 H-41 - Pectin 2. wash and press 52.7 H-41 - Pectin 3.wash and press 53.3

The data in Table 28 indicates that a single wash with 80% isopropanolfollowed by a single pressing at 4 bar is enough to increase the drymatter of the pectin waste to above 50%.

Example 17 Pectin Waste Material Washed Once with DifferentConcentrations of Ethanol

In this experiment, pectin waste material was washed once with differentconcentrations of ethanol and subsequently pressed once with a screwpress at 4 bar counter pressure.

The results are listed in Table 29.

TABLE 29 Dry Matter of Pectin Waste Washed with Different Concentrationsof Ethanol Waste Dry Sample Comment Ethanol % Matter % Comment H-6 -Pectin Fresh waste 0 13.9 H-6 - Pectin Wash and 40 Not press pressableH-6 - Pectin Wash and 65 44.6 press H-6 - Pectin Wash and 73 40.6 press

This data in Table 29 shows that a combustible waste material isproduced when using a concentration of ethanol of at least about 60%.

Example 18 Carrageenan Waste Material Washed Once with Isopropanol andEthanol

Carrageenan waste is another example of material containing a waterbinding polymer. Such waste is traditionally used as soil improvement.In this experiment, carrageenan waste material was washed with 40%isopropanol and pressed on screw press. Also, carrageenan waste materialwas washed with 60% ethanol and pressed on screw press.

Results are listed in Table 30.

TABLE 30 Dry Matter of Carrageenan Waste Washed with Isopropanol andEthanol Waste Dry Sample Comment IPA % Ethanol % Matter % C-128 -Carrageenan Fresh waste 0 0 30.5 C-128 - Carrageenan Wash and 40 0 54.7press C-128 - Carrageenan Wash and 0 60 46.3 press

The data in Table 30 indicates that washing with isopropanol or ethanoland pressing carrageenan waste leads to a high dry matter in the wastemaking it combustible. Also, the results indicate that isopropanol canbe used in lower concentrations than ethanol.

In summary, Examples 15-18 show that a process according to embodimentsof the present invention can be utilized to increase dry matter ofpolysaccharide containing waste material to provide for a combustiblematerial to save energy and to reduce CO₂ emission.

Example 19 Sugar Beet Waste Material Washed with Isopropanol

In this example, sugar beet waste obtained after extraction of sugar wasused according to an embodiment of the present invention. The dry matterof the sugar beet waste was 28.0%, and in a first test, 15 kg. sugarbeet waste was washed for 20 minutes with 30 liters 40% isopropanol. Thewashed sugar beet waste could not be pressed on the screw press used inthe previous examples, and when pressed on a double screw press (StordBard), the dry matter reached 26.7%. Similarly, when the washed sugarbeet waste was run through a conventional decanter, the dry matter ofthe resulting material reached 28.2%. Without being bound of theory, itis believed that the denser structure of sugar beet waste require higherconcentrations of alcohol and probably longer washing times.

Consequently, a series of washings were performed using 15 kg sugar beetwaste and 30 liters isopropanol in each series. Washing was conductedfrom 1 hour to 45 hours and dry matter of the resulting material wasdetermined after being pressed once and twice on the screw press used inprevious examples.

TABLE 31 Dry Matter of Washed and Pressed Sugar Beet Waste Washing No ofTime Hours Pressings Dry Matter % Dry Matter % 45 1 48.3 45 2 48.3 24 147.9 24 2 52.2 12 1 48.5 12 2 51.1 6 1 46.4 6 2 50.3 3 1 45.5 3 2 46.8 11 49.7 1 2 51.1

The data in Table 31 shows that the dry matter increased to about 50% byweight of the beet waste material after washing in 80% by weightisopropanol for one hour, and that a second pressing increased the drymatter marginally. This example shows that when dealing with denserpolysaccharide containing materials, washing with alcohol for a longerperiod than about 20-30 minutes may be necessary.

Example 20 Two Step Alcohol Wash and Pressing of Conventionally WaterWashed Fresh Peel

In this example, about 20 kg juiced orange peel was first washed with 40liters water at room temperature, and then processed according toExample 14 using ethanol for washing.

TABLE 32 Results from Two Step Alcohol Wash of Conventionally WaterWashed Orange Peel Peel EtOH EtOH Peel Dry Sample Kg Kg Density % Matter% Pectin Yield % 1151-108-A0 18.4 30.1 11.3 1151-108-A3 19.3 24.5 5223.5 1151-108-A4 19.3 25.1 66 22.8 1151-108-A-press 4.7 37.6 66 52.929.0 1151-108-B0 19.7 24.6 1151-108-B3 22.5 34.6 44 22.4 1151-108-B420.9 26.8 64 21.68 1151-108-B-press 5.5 39.2 62 54.4 30.9 1151-108-C019.4 24.5 1151-108-C3 21.1 36.4 43 22.5 1151-108-C4 19.5 26.0 63 23.21151-108-C-press 5.0 38.8 60 53.3 29.8

Comparing with Table 26 of Example 14, it is indicated that a firstconventional water wash resulted in lower peel dry matter and lowerpectin yield. Without being bound of theory, this may be explainedthrough a loss of pectin during the first conventional water wash.

Table 33 lists the laboratory analysis of the resulting pectin products.

TABLE 33 Analysis of Resulting Pectin Products Residual Clarity ClaritySugar IV DE GA Cold Hot CS + Ca²⁺ CS − Ca²⁺ Pectin % dl/g % % % T % T pHcP cP 1151-108-0A 39.0 4.379 66.9 83.2 83.7 84.9 3.28 153.5 12.61151-108-A-pres 8.5 3.847 68.8 84.8 92.1 93.1 3.07 14.8 10.51151-108-B-pres 7.7 4.498 68.7 83.2 85.1 86.0 3.24 21.4 12.51151-108-C-pres 6.7 4.065 68.7 85.6 85.6 90.8 3.08 17.5 11.3

The data in Table 33 indicates that a pre-wash with water appears tohave reduced residual sugar somewhat when compared with the four stepalcohol wash in Example 13. Further, the molecular weight measured asintrinsic viscosity is lower than that in Table 13. Without being boundby theory, this may be due to dissolution of some high molecular weightpectin during the water wash. However, other features of the resultingpectin products are on par with those found in Example 13. Thus, apre-wash with water has the advantage of further reducing the residualsugar in the peel, but suffers with respect to peel dry matter, pectinyield and molecular weight of resulting pectin product.

While the invention has been described in detail with respect tospecific embodiments thereof, it will be appreciated that those skilledin the art, upon attaining an understanding of the foregoing, mayreadily conceive of alterations to, variations of, and equivalents tothese embodiments. Accordingly, the scope of the present inventionshould be assessed as that of the appended claims and any equivalentsthereof.

We claim:
 1. A dewatered biomass material comprising a polysaccharide,wherein the dewatered biomass material comprises dry matter in an amountfrom 35% to about 60% by weight of the dewatered biomass material and aresidual sugar content from about 3% to about 30% by weight of thedewatered biomass material.
 2. The dewatered biomass material of claim1, wherein the dry matter is from about 50% to about 60% by weight ofthe dewatered biomass.
 3. The dewatered biomass material of claim 1,wherein the residual sugar content is from about 3% to about 15% byweight of the dewatered biomass material.
 4. The dewatered biomassmaterial of claim 1, wherein the biomass material is selected from thegroup consisting of citrus fruit peel, apple pomace, sugar beet residuefrom sugar production, sun flower residue from sun flower oilproduction, potato residue from starch production, red seaweed, andbrown seaweed.
 5. A dewatered citrus peel comprising dry matter in anamount from 35% to about 60% by weight of the dewatered citrus peel anda residual sugar content from about 3% to about 30% by weight of thedewatered citrus peel.
 6. The dewatered citrus peel of claim 5, whereinthe dry matter is from about 45% to about 60% by weight of the dewateredcitrus peel.
 7. The dewatered citrus peel of claim 5, wherein the drymatter is from about 50% to about 60% by weight of the dewatered citruspeel.
 8. The dewatered citrus peel of claim 5, wherein the residualsugar content is from about 3% to about 20% by weight of the dewateredcitrus peel.
 9. The dewatered citrus peel of claim 5, wherein theresidual sugar content is from about 3% to about 15% by weight of thedewatered citrus peel.
 10. The dewatered citrus peel of claim 5, whereinthe citrus peel is selected from the group consisting of an orange peel,lemon peel, lime peel, and grapefruit peel.